Dubai has opened the world's tallest skycraper, renaming it the Burj Khalifa
in honour of the man who bailed the financially troubled Gulf city-state out
of its debts.

Surprising those gathered on Monday evening for an opening ceremony lit up by fireworks, the Burj Dubai, whose height was officially given as 828 metres or 2717 feet, became the Burj Khalifa - or Khalifa Tower.

Sheikh Khalifa bin Zayed al-Nahyan is the ruler of the neighbouring emirate of Abu Dhabi, and president of the United Arab Emirates. He and his brothers personally intervened last month to lend Dubai £6 billion to pay off the pressing debts of one of Dubai's biggest state-owned companies.

The tower was launched by Dubai's ruler, Sheikh Mohammed bin Rashid al-Maktoum, with a spectacular display of fireworks, which fired out from the sides of the building all the way up its tubular spire to its peak.

Its inauguration, on the fourth anniversary of the sheikh's accession to the emirate, has brought a much-needed feeling of festivity to Dubai, which has been battling all year with a debt crisis caused by a collapse in property prices amid the world financial crisis.

The tower has become symbolic of the emirate's woes: historians have pointed out that an obsession with skyscrapers is a good sign of an economic bubble. The Empire State Building was commissioned when New York's stock market was at its peak in the 1920s, and opened after the Wall Street Crash.

The passion for tall buildings moved to Hong Kong and other parts of Asia in time for the 1997 financial crisis.

The tower's exact height had been long kept a secret, with the builders, the specialist Chicago skyscraper firm of Skidmore, Owings and Merrill, allowed and even encouraged to keep going until they thought they could go no further.

At 2,717 feet, it is a full 1,046 feet higher than the world's previous highest occupied building, the Taipei 101 in Taiwan, and 654 feet higher than the tallest man-made structure, the KVLY-TV tower in North Dakota, America, a broadcasting mast.

It will contain more than 1,000 apartments, an Armani-branded hotel, and offices up to the 160th floor. Financial analysts are looking forward to discovering how many have been let, and at what cost, given that property prices have halved in the city in the last year.

The top 40 floors - growing ever smaller towards the top - will be occupied by the tower's service centres.

The first chance to see the interior - and the view - came with the opening of an observation deck on the 124th floor on Monday.

It provides a good platform from which to view the city's achievements, for good or ill.

After ascending in a single lift ride at more than 30 feet per second, visitors who pay £17 will be able to see the tops of the city's other skycrapers hundreds of feet below.

They will, in fact, be able to see the whole "World" spread out at their feet - the archipelago of artificial islands out in the Gulf which is supposed to be a base for luxury villas, hotels and shopping developments but which is currently almost entirely empty.

This being Dubai, they will also have the opportunity to shop. The souvenir stall sells a range of "Burj Dubai" tee-shirts, with some noticeable additions: 299 dirhams, just short of £50, is the cost of a drink of water, as the bottles have a portrait of the tower and its name picked out in diamante.

Visitors will have a stark vision of Dubai's economic growth in the last three decades - from desert to the tower's south to its thriving port and commercial centre to the north and east.

Mohammed Alabbar, the chairman of the tower's developer, Emaar Properties, showed he was aware of the irony of the tower's opening at the nadir of the city's fortunes.

"Crises come and go. And cities move on," he said. "You have to move on. Because if you stop taking decisions, you stop growing."

The city's defenders point out that even if Manhattan and Hong Kong suffered financial crises when their most celebrated buildings opened, they have not done badly since. North Korea, on the other hand, has few skyscrapers.